轴径向气隙混合磁路多边耦合电机轴向励磁绕组的反电势及其位置传感器机理

无传感器控制是比较理想的电机驱动模式,是电机及电力传动领域的研究热点之一.该文在混合式步进电动机的基础上提出一种轴径向气隙混合磁路多边耦合电机,电机在提高单位体积出力的同时,在不增加传感器的条件下实现了电机的闭环控制.这种电机的结构特点决定了电机控制的灵活性,轴向励磁绕组既可以控制轴向磁通,还可以兼作转子位置传感器.该文结合轴径向气隙结构混合磁路多边耦合电机的特点,在对该种结构电机轴向绕组谐波反电势解析分析和实验研究的基础上,提出基于轴向补偿励磁线圈同时作为电机位置传感器的思想,探求了轴向励磁补偿控制绕组的传感器机理,并给出具体电路,确认了其实现的可行性.研究表明,当定子绕组三相同时通有电流的时候,轴向线圈的反电势频率是定子绕组电势的3倍,根据这个反电势信号,轴径向气隙结构混合磁路多边耦合电机可以方便的实施无传感器控制.

POSITION SENSOR PRINCIPLE AND AXIAL EXCITING COIL EMF OF AXIAL AND RACIAL AIR GAP HYBRID MAGNET CIRCUIT MULTI-COUPLING MOTOR

An axial and radial air gap hybrid magnet circuit multi-coupling motor is produced based on hybrid stepping motor. A close loop control is achieved on this kind of motor drives without extra-sensor, besides the increasing of the torque per volume. So the motor can be drove as sensorless switched reluctance motor with bigger torque output. The control of axial and radial air gap hybrid magnet circuit multi-coupling motor is flexible profited from its novel structure with axial coils which can be used as position sensor at the same time that the air gap flux can be adjusted by them. Based on harmonic analysis and experiment on electro-magnetic force in the axial coil, the rotor position detecting principle of axial and radial air gap hybrid magnet circuit multi-coupling motor is developed, which is according to the electro-magnetic force of the axial coils. The rotor position detecting and shaping circuits are presented. The analysis and experiment show that the frequency of electro-magnetic force in axial coils is 3 times of that in stator coils when 3 phase stator armatures are powered simultaneity. So the sensorless control on the motor is achieved conveniently.